docs(changelog): date entries by when they land, add the two missing ones

CLAUDE.md

@@ -50,7 +50,9 @@ When in doubt, default to `recommended`, not `required`. The bar for `required`
 
 **Always link to the page(s) inline.** An "added a page on X" entry must link X to its `/spec/<category>/<slug>/` URL _in the sentence_ — never trail off with a link to the `/spec/` index. List every page added, each linked.
 
-Do **not** log: typo fixes, refactors, CI/tooling, dependency bumps, OG tweaks, new analytics events, header changes, or any site behaviour invisible on a spec page. Use real dates (British English in the body) and keep each entry to one-to-three sentences.
+Do **not** log: typo fixes, refactors, CI/tooling, dependency bumps, OG tweaks, new analytics events, header changes, or any site behaviour invisible on a spec page. British English in the body, and keep each entry to one-to-three sentences.
+
+**`date` is the day the entry lands on `main`, not the day it was written or the day the underlying standard moved.** This is _our site's_ changelog: it records when this spec changed, not when the world did. A PR authored on the 23rd and merged on the 31st is dated the 31st — so if a PR sits for a few days, re-date the entry (and rename the file to match) before merging. Mention the standard's own date in the body if it matters. The filename is `<date>-<slug>.md` and its stem becomes `entry.id`, which is both the `<li>` anchor on `/changelog/` and the `#`-link in the RSS feed — so renaming an entry that is already live re-delivers it to subscribers as a new item. Re-date before merging, not after.
 
 **When you are unsure whether a change warrants an entry, ask the user — do not silently skip it.** The clear-cut cases decide themselves (a new page always gets one; a typo fix never does). For anything in between — a partial rewrite, a citation overhaul, a reworded summary, a status nuance that isn't a full promotion/downgrade — surface it: _"This change to X is borderline for the changelog — log it as a `changed` entry, or leave it out?"_ and let them call it.
 

src/content/changelog/2026-07-31-aipref-attach-expired.md

@@ -0,0 +1,8 @@
+---
+title: Half of the AI-preferences work has stalled, and the page says so
+date: "2026-07-31"
+type: changed
+relatedSlugs: [content-signals, robots-for-ai-crawlers]
+---
+
+The IETF vocabulary draft behind AI content preferences is alive, but the attachment draft — the half that would define how a site binds those preferences to content over HTTP — expired on 1 May 2026 and has not been reposted. [Content signals](/spec/agent-readiness/content-signals/) now separates the two, so the page is honest that the `robots.txt` line you can write today rests on the IAB Tech Lab specification and validator convention rather than a live IETF draft.

src/content/changelog/2026-07-31-aria-in-html.md

@@ -0,0 +1,8 @@
+---
+title: The four rules of ARIA, and the document that is now normative
+date: "2026-07-31"
+type: changed
+relatedSlugs: [aria-usage, semantic-html]
+---
+
+"Using ARIA" became a Discontinued Draft in February 2026, and it lists four rules — not the five [ARIA — first rule of ARIA](/spec/accessibility/aria-usage/) claimed. The page now cites [ARIA in HTML](https://www.w3.org/TR/html-aria/), which reached W3C Recommendation on 15 April 2026 and is the normative statement of which roles are valid on which elements; the answers are not always the intuitive ones, since `role="button"` on an `<a href>` is permitted while `<textarea>` accepts no role other than the `textbox` it already has.

src/content/changelog/2026-07-28-mcp-2026-07-28.md → src/content/changelog/2026-07-31-mcp-handshake.md

@@ -1,6 +1,6 @@
 ---
 title: MCP dropped the handshake, so the page describing it had to change
-date: "2026-07-28"
+date: "2026-07-31"
 type: changed
 relatedSlugs: [mcp-and-tool-discovery, deprecation-and-sunset, agent-readiness-overview]
 ---

src/content/changelog/2026-07-28-tdmrep.md → src/content/changelog/2026-07-31-tdmrep.md

@@ -1,6 +1,6 @@
 ---
 title: Reserving mining rights is a legal act, not a crawler block
-date: "2026-07-28"
+date: "2026-07-31"
 type: added
 relatedSlugs: [tdmrep, content-signals, robots-for-ai-crawlers]
 ---

src/content/changelog/2026-07-30-websub.md → src/content/changelog/2026-07-31-websub.md

@@ -1,6 +1,6 @@
 ---
 title: Added a page on WebSub
-date: "2026-07-30"
+date: "2026-07-31"
 type: added
 relatedSlugs: [websub]
 ---